1. Field of the Invention
The present invention relates to a supporting structure for a motor rotor that includes a support member secured in the axle tube for supporting an end of the rotor shaft, thereby allowing stable rotation of the rotor.
2. Description of the Related Art
Applicant's U.S. patent application Ser. No. 09/366,636 filed on Aug. 4, 1999 discloses positioning structures for a motor rotor, wherein an axle tube 3 is extended through a stator bobbin 1 and a circuit board 2 and includes a bearing 31 mounted in the axle tube for pivotally support a rotor shaft 41 of the rotor 4. A support element 32 is mounted to a lower end of the axle tube 32 for supporting a lower end of the rotor shaft 41. Thus, the rotor shaft rotates stably about a fixed axis. Rotational noise of the motor is lowered and life of the motor is lengthened.
Nevertheless, a pressing process is required to securely position the support element 32 in the axle tube 3 to thereby prevent disengagement of the supporting element 32. During assembly, the axle tube 3 is incapable of resisting the pressure from the support element 32 at pressing process and thus the stator bobbin 1 and the circuit board 2 may be loosen and displaced from the axle tube, which is undesired.